The multiplicity of commands and the diversity of means accessible to a vehicle driver have increased to the point that many vehicles have on their steering wheel, or on an offset satellite, one or more rotary scroll wheels which can be operated by a touch of the driver's thumb. These scroll wheels connected to displays or screens make it possible to scroll through the options of a menu of commands such as radio stations or names in an address book. In order to confirm a choice, the user must press the scroll wheel and push it in slightly like a conventional pushbutton.
From DE102007038580A1 is known a command selector of this type of which the rotary scroll wheel entrains a spur gear train and a disc with deep indentations, the rotation of which is detected by an optical sensor. The scroll wheel is further arranged in a support, and pressing on the scroll wheel displaces the scroll wheel and the support which actuates a switch of a printed circuit board. In a conventional manner, the switch is integrated in an elastomeric dome of a cover covering the printed circuit board.
The functionalities exist and the requirements now relate to the compactness of the device, the availability of commands and the tactile feel experienced by the user. It becomes important to propose compact selectors capable of being accommodated in spaces which are not only restricted, but also difficult to fit because they have convex or inclined surfaces. Furthermore, pushbuttons or displays or even other rotary selectors must be able to be placed in the vicinity thereof.